After the illegals began to put down roots in the U.S. ten years earlier, they received an encrypted message from Moscow Center, the headquarters of their KGB-spinoff service, known as the SVR:

“You were sent to USA for long-term service trip. Your education, bank accounts, car, house, etc. – all these serve one goal: fulfill your main mission, i.e. to search and develop ties in policymaking circles in US and send intels to C [intelligence reports to Moscow Center].”

Little did the Russians know, the FBI was on to them from the get-go. What followed was the longest-running and most successful counterintelligence investigation ever run by the bureau.

When federal agents rounded them up from Seattle to New York at the end of June 2010, they were flown to New York to await trial on espionage charges. But the U.S., which spies on Russia with equal gusto, knew that could cause trouble for its own agents in Moscow.

So with President Obama’s blessing, they arranged the first major spy swap since the Cold War. President Vladimir Putin would get his SVR officers back, safe and sound; and the U.S. and Great Britain would get back four Russian spies who had proved valuable to the CIA and other American intelligence agencies.

One of the spies the U.S. got back, a former Russian SVR colonel, had given the CIA information about Harold James “Jim” Nicholson, which led to his 1996 arrest and subsequent imprisonment in Oregon.

Well, I’ve said too much already. To learn the identity of that Russian spy, you’ll have to read the book.

To whet your appetite, here's a video of Anna Chapman meeting with whom she thought was a fellow Russian spy. (Turns out, he was with the FBI.) Note how she keeps covering her mouth as she speaks.